Field of the Invention
This invention relates to a humidification chamber for a respiratory assistance apparatus that provides a stream of humidified gases to a user for therapeutic purposes. The respiratory assistance apparatus may provide respiratory assistance to patients or users who require a supply of gases for respiratory therapies such as, but not limited to, humidification and/or flow therapy, Positive Airway Pressure (PAP) therapies, including but not limited to CPAP therapy, Bi-PAP therapy, and OPAP therapy, and which are typically used for the treatment of diseases such as Obstructive Sleep Apnea (OSA), snoring, or Chronic Obstructive Pulmonary Disease (COPD).
Description of the Related Art
Respiratory assistance devices or systems for providing a flow of humidified and heated gases to a patient for therapeutic purposes are well known in the art. Systems for providing therapy of this type typically have a structure where gases are delivered to a humidifier chamber from a gases source, such as a blower (also known as a compressor, an assisted breathing unit, a fan unit, a flow generator or a pressure generator). As the gases pass over the hot water, or through the heated and humidified air in the humidifier chamber, they become saturated with water vapour. The heated and humidified gases are then delivered to a user or patient downstream from the humidifier chamber, via a patient interface comprising a flexible gases conduit and a user interface.
FIG. 1 shows a schematic view of one type of known respiratory assistance system 1 for delivering humidified and heated gases to a patient. The system 1 comprises a housing 2 containing a blower unit 3 and humidifier unit 4. In operation, atmospheric air 5 is drawn into the blower unit 3. The blower unit 3 generates a pressurized air or gases stream which is delivered to the inlet 7 of a humidification chamber 8. The humidification chamber 8 comprises water and is heated by a heater pad 9. The humidified and heated gases stream 10 exits the humidification chamber via an outlet 11 of the humidification chamber and is delivered to the patient or user 12 via a flexible hose or gases conduit 13 and user interface 14 as shown. The blower unit and humidification unit are typically connected via a series of connectors and/or conduits to allow gases to pass from the blower unit to the humidifier unit.
The user interface 14 shown in FIG. 1 is a nasal mask, covering the nose of the user 12. However, it should be noted that in systems of these types, a mask that covers the mouth and nose, a full face mask, a nasal cannula, or any other suitable user interface could be substituted for the nasal mask shown. A mouth-only interface or oral mask could also be used. Also, the patient or user end of the conduit can be connected to a tracheostomy fitting, or an endotracheal intubation.
The humidification chamber 8 typically comprises a rigid plastic receptacle or container that can be filled with a volume of water. In one known form, the base of the humidification chamber comprises a circular thermally conductive metal heater plate that is fixed within a complementary aperture provided in the base of the humidification chamber via overmolding of the plastic base about the peripheral edge of the heater plate. The overmolding forms a seal at the interface between the perimeter edge of the heater plate and surrounding plastic base surface of the chamber. In use, the heater plate contacts a heater pad or heater base upon which the humidification chamber rests and heats the volume of water in the chamber via conduction. Overmolding to couple the heater plate into the base of the plastic chamber can be a complicated manufacturing process and difficult to control.
In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior art, or form part of the common general knowledge in the art.
It is an object of the present invention to provide an improved humidification chamber, or to at least provide the public with a useful choice.